I'm not completely sure. I think the broad frequency designations are the same, but then I see ATT bands listed as US versions of phones.

Regardless, the last Google Nexus was available in a T-Mobile version and I think the new one is a single model which supports both. And the price is within the range of Sony's lineup. Obviously Google can expect higher sales via self-promotion, but you would expect Sony to make at least one out of several.

Question: does T-Mo now have a roaming agreement with AT&T whereby 1900 (WCDMA Band II) is offered? This is probably only in major urban areas at this point. T-Mo CTO blog said that iPhone users on T-Mo net will see better performance with 1900 access!

OK. So, T-Mo LTE will be AWS/1700/Band IV in future. 1900MHz will be 3G/HPA+ services. 1900MHz/Band II will support WCDMA voice/data on T-Mo. So, the Sony Xperia will work on T-Mo metro areas. Correct?